Decatur Yellow Bikes is a non-profit organization that takes donated bikes and fixes them up for people to ride. You just pay a $25 deposit, and you can take a bike home with you. If you decide to keep it, it's only $25 out of your pocket, if not, you can get your deposit back. If you ever have any problems, you can go and get it fixed for free. It is all volunteer run, so they need as many volunteers they can get, even if you don't know much about bicycles. The purpose of the organization is to encourage more bicycle riding, which is a great idea, especially in this time of high gas prices.